An acca insurance calculator works out the expected value of accumulator insurance offers, where the bookmaker refunds your stake as a free bet if exactly one leg of your acca loses. Enter your acca stake, the decimal odds for each leg and the refund type, and the calculator shows EV, potential profit and the refund amount across all three outcome scenarios.
If you are using the offer for matched betting, after insurance triggers use the matched betting calculator to find the lay stake that converts the free bet to guaranteed cash.
How to Use the Acca Insurance Calculator
- 1Enter your acca stake - the amount you are placing on the accumulator at the bookmaker.
- 2Add selections and decimal odds - enter the decimal odds for each leg. Use the plus button to add more legs and the trash button to remove one.
- 3Choose refund type and max refund - select whether the insurance pays as a free bet (most common) or cash, and enter the bookmaker's maximum refund cap if one applies.
- 4Read expected value and profit scenarios - the readout shows EV, total acca odds, profit if all legs win, and the refund amount triggered by exactly one loss.
Acca Insurance: A Worked Example
Setup
$20 stake on a 5-leg acca at total odds of 30.0. Bookmaker offers money-back as free bet if exactly one leg loses. Max refund $20.
Profit if all win
$20 x 30.0 = $600 return. Profit: +$580.
Refund if one leg loses
$20 free bet. Converted at ~80% via matched betting: ~$16 cash.
If two or more legs lose
No refund. Net: -$20.
EV calculation
With each leg at roughly 50% implied probability, exactly-one-failure probability is around 16%. Expected value added by insurance is approximately 16% x $16 = +$2.56 per run of the offer.
How to Value Acca Insurance Offers
Acca insurance is only worth doing if the probability of exactly one leg failing is meaningful. A 5-leg acca where each leg has 70% win probability gives roughly a 36% chance of exactly one failure. With a $20 free bet converting to $16 cash, that is approximately $5.76 expected value added per offer run.
Shorter accas (3 to 4 legs) raise the one-failure probability but reduce the combined odds and therefore the nominal free bet value relative to stake. Longer accas (6 or more legs) lower the trigger probability and can make the offer negative EV even though the headline refund looks attractive.
Common Mistakes with Acca Insurance
- xIgnoring the "exactly one leg" condition. Some bookmakers require exactly one leg to lose. If two legs fail, there is no refund. Read the terms before placing.
- xNot checking minimum odds per leg. Most acca insurance offers require each leg to be at minimum odds, typically 1.50 to 1.70. Including lower-priced legs can invalidate the offer.
- xHigh acca odds inflating the lay liability. A 50.0 acca requires approximately $50 lay liability per $1 stake at similar exchange odds. Confirm you have sufficient exchange funds before placing.
Frequently Asked Questions
What is acca insurance in matched betting?
Acca insurance is a bookmaker promotion that refunds your stake (usually as a free bet) if exactly one leg of your accumulator loses. In matched betting, you lay the full acca on an exchange and convert the free bet to cash if insurance triggers, locking in a return regardless of the acca result.
Is acca insurance worth doing?
Yes, when the probability of triggering insurance is significant. A 5-leg acca with each selection at around 70% win probability has roughly 36% chance of exactly one failure. Over multiple offer runs this converts to consistent positive expected value.
How many legs should I include in an acca insurance offer?
Five legs is the most common choice. Fewer legs raise the trigger probability but reduce combined acca odds and the nominal free bet value relative to stake. More legs lower trigger probability and raise lay liability, often making the offer less attractive.
What happens to my lay bet if the acca wins?
If the acca wins the bookmaker pays out the full return, which covers your exchange lay liability, leaving you roughly flat. The profit from the strategy comes from triggering insurance on a separate run of the offer rather than from a winning acca.